I got approved to try Google Apps today. I decided I'd try out using Gmail as my mail server on the CoasterBuzz.com domain. So far, I like what I see.
It's easy enough to handle the e-mail switch. You set your DNS MX records to point to a few different domains of theirs, and off you go. I was receiving e-mail there in ten minutes.
I have a couple of different motivations for checking this out. First of all, I love the searchability of Gmail, and the fact that it's simply everywhere. And with POP access, you can download the mail and "own" it even if Gmail were to disappear or start charging for it.
The other thing is that I really kind of want to get e-mail service off of my server. I'm already doing around 30% average peak CPU utilization (because of some really bad code that's three years old), so whatever I can pull off will help.
If I like what I see, I may switch over my primary domain as well. We'll see!